Water heater



Julyv 28, 1931 I F. s. coRBUs WATER HATER Filed Aug. 16. 1928 lill I I I I ...Illl

Patented July 28, 1931 'UNITED ,STATES PATENT OFFICE `I'REZDIIIIEIGK G. GORBUS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNB, T0 DAVID I.. NEWBOLR OF PHILADELPHIA, PENNSYLVANIA WATER HEATER Application led August 16, 1928. Serial No. 800,050.

This invention relates to improvements in water heaters, and more particularly to the construction of the dome of the combustion chamber of such heaters.

,5 Attempts have been made to provide the dome or header for the combustion chamber of heaters of this character, when made of steel, with auxiliary heating means. consisting of a number of studs or projeetlons distributed either regularl or at random, throughout the surface o the dome on both sides thereof, and therefore extending partly into the combustion chamber, and partly into the water space or tank. In steel headers or domes, so far as I am aware, thestuds have extended through the dome, maklng 1t necessary to perforate it, the .method of securing the studs being by rivetmg them or securing them by jamb nuts or providing the studs with threads, cooperating with threads in the dome, and in some cases 1t appears that the studs have apparently been driven in the dome with a tight t, but 1n no case, so far as I am aware, have these studs been secured to the dome by welding, electrically or otherwise. None of the methods heretofore employed have been successful, due to the fact that where the studs pass through the dome and are secured by ao methods other thanY welding,the effect is that the dome .is erforated and such perforations are not e ectively closed by the studs and due to the expansion and contraction of the metal of which the dome is made, and the studs or projections are made, leaks have invariably occurred to a greater orless extent, accordin to the manner or method of attachment o the plugs. In my co-pending application Serial Numberv221,069, iled September 2l, 1927, I haveshown a method of applyingy these studs to the dome of the combustion chamber by a swaging or riveting process and notwithstanding the fact that the metal employed for the manufacture of the studs has, as stated in said application, the same coefficient of expansion as the material of the dome, trouble has been experienced from leaks.

50 j iIn an apparatus of this kind, it is obvious that unless the dome or metal separating the combustion chamber from the water tank is absolutely leakless, the eilicient operation of the .device is impossible. In View. of the IOregOmg, and to overcome the objections lntimated, I have devised a construction wherein these studs may be attached to both sldes of the dome, without the necessity of perforating the metal of the dome, and test has demonstrated that an absolutely leakless structure is rovided, and even where the dome is per orated or punctured, and the studs passed through theperforations and welded, satisfactory results may be att ined, the di'erence between the degrees oiiL success being due the fact that the studs are Welded to the dome and both being constructed of metal having the same coeicient of expansion, become virtually and substan- -tially integral.

In view of the foregoing, the invention contemplates the provision of a dome having spotwelded 'thereto on both sides thereof, preferably, a number of studs or projections, those on the bottom extendin into the combustion chamber and those a ove extending into the tank, the studs being of the same material as the dome and having the same coeilicient of expansion, so that under operative conditions involving expansion and con# traction, the homogeneity of the studs and dome eliminates the tendency of separation of these parts, thus eliminating the possibility of leaks. Secondarily, the invention contemplates the use of studs that may extend through the material of the dome, but which may be welded in position therein. t. In the drawings illustrating the inven- Figure 1 is a view partially in section and partially in elevation of a water heater having a dome embodying my invention.

Figure 2 is a detail perspective view of one of the heat augmenting studs or elements.

Figure 3 is a similar view of a modified form of said element, used upon the top surface of the dome. l

Figure 4 is a detail sectional view of a portion of the dome showing the form of stud shown in Fiigure 3 on the upper surface of the dome, an a stud like that shown 1n Figure 2 on the lower surface.

igure 5 is a View showin portions of the arms and the electrodes o? a spot welding machine, by which the studs or projections are welded to the dome plate.

'Referring to the drawings, the numeral 1 designates the outer casing, 2 the wall of the water tank, there being between `the two walls a filling-of insulating material 13, of asbestos or the like, the filling forming an insulating jacket., The lower end of the tank is closed by a cap 4, with the exception of a suitablev number of holes 4 for the purpose of admitting air to the burner.

The numeral 5 designates the dome of the combustion chamber 6, which chamber is formed by the bottom of the tank, and the said dome, and contains a gas burner 7 of any approved type, the burner being 'supplied by a pipe 8 connected in the usual way with a suitable thermostat 9 employed to regulate the fiow of gas to the heater, according tothe temperatures desired. The thermostat and its connections, burner, etc., form no part of the invention, and need not be further considered.

Let into the dome at properplaces, are a number of heat conducting tubes or iues 10 which extend entirely to lthe top of the tank,

-the tubes being open at their tops and bottoms, there being provided in the top of the heater, means for conducting the products of combustion to a single outlet, which may be of usual form and which is not shown. As shown in Figure 1 baiiies 11 may be employed in the form of undulated metal strips that are suitably supported, preferably at the top of the tubes and'extend substantially throughout the length of the tubes, these being Vfor the urpose of retardingor b'aifling the too rapid flow of heat through the tubes for the obvious purpose of utilizing the heat forthetmore rapid heating of the water.' f

The numeral V12 designates a plurality of studs and in the form shown in Figure 1 of the drawing, these will usually be identical both for the topof the dome and the under side thereof. As vshown in Figure 2, these lstuds or projections are normally-.slightly rounded at their blunt ends, which rounded portion is obliterated or fused away in theV process or method of attaching them to the surface of the dome, when the welding current is applied. These studs or projections arenumerous and are distributed throughont virtually the entire surface of the dome, both at the bottom 'and top thereof. The

'lower studs extend into the combustion chamber 6 in position to contact with the iiame of the burners and the upper studs extend into the water space of the tank 2. Preferably these bottom and top studs are in and forming heat au attached respectively; the electrodesA C and D. One or both of the arms A and B and the electrodes carried thereby are capable of a wide range of separation from the other, so that after the studs are welded to the dome, the electrodes are withdrawn from said studs.

Referring to Figure 4 it will be noted that the lower stud corresponds with those on the under side of the dome in Figur whereas the upper stud is different, the latter consisting of a short hollow, tapered pipe section 13, of the same general external shape as the studs 12. The pipe sections are open at their upperends, as indicated at 14 and extending into the water chamber ofthe burner, are at all times, during the operation of the heater, lled with water, thus providing an additional heating surface composed of the inner and outer surfaces of the pipe sections.

As shown in Figure 4, the hollow studs are spot welded to the dome, preferably at the same time the stud or projection is welded to the lower surface of the dome.

It will be noted by reference'l to Figures 3 and 4, that the modified form of studl for use on the u per surface of the dome is as intimated, o the same general externa shape as the lower' studs, thus enabling electrodes ofthe same shape to be used in welding both forms. j

From the foregoing, it will be seen that the preferred construction and'method described, eliminates the necessity of perforating the dome, thus providing an eiicient heat ali4 leo

augmenting means whereby the heat is vcon-r ducted from the combustion chamber to the water in the tank, and greatly augmented by reason of the increased heating surface in both the chamber and the tank. v

Having thus described my invention, what Iclaim'isr- 1. A heater of the class described, comprising a'tank closedat itstop and bottom, a combustion chamber below the tank including an imperforate dome forming a closure forthe bottom of the tank, said dome being provided with numerous studs spotvwelded on the upper and lower surfaces thereof, and in vertical line with each other, i enting .means, and means for supplying eat said combustion chamber.

2. A heater of the class described, comprising a tank closed at its bottom and top, a combustion chamber below the tank -in cluding an imperforate dome forming a closure .for the bottom of the, tank, said lio ' lao dome being provided on its upper side with numerous hollow studs open at their ufper ends, said studs bein welded to the ome surface, and means or supplying heat to 5 the combustion chamber.

In testimony whereof I ax my signature.

FREDERICK G. CORBUS. 

